To make the crepes: Whisk the flours, salt, milk, buttermilk, butter, and eggs together in a large bowl until very smooth. To save arm power, you can blend the ingredients in a blender instead. Let the batter sit for at least 1 hour at room temperature and up to 1 day in the refrigerator. Rub a small dab of butter (1/2 tablespoon or so) onto the bottom of a 9- or 10-inch nonstick crepe pan or saute pan over medium heat and wait until it melts completely. (Too much butter will make for a soggy crepe.) Pour 1/4 cup of the batter into the hot pan and tilt it in a circular motion to ensure the batter spreads out into an even layer. Cook over low heat until the edges start to pull away from the pan, about 2 minutes. Using a nonstick spatula, carefully flip and cook the other side until golden brown, about 1 minute. Lay the crepe on a large plate and repeat until you`ve gone through all of the batter (it`s okay to stack the crepes on the plate). If the crepe pan starts to get too dry, add another little dab of butter. I tend to cook these quickly while the plums are sauteing and assemble them right then, but if you`re chatting with friends and taking your time, keep the finished, unfilled crepes warm in a 200°F oven until ready to assemble. To saute the plums: In a medium saucepan over medium heat, melt the coconut oil. Add the vanilla and honey, swirl the pan so they combine with the coconut oil, and then add the plums. Saute until juicy and warm, 2 to 3 minutes. To assemble: For each crepe, gently fold the crepe in fourths (fold in half, then in half again) and dollop 1 to 2 tablespoons of the Honeyed Ricotta and a few sauteed plums on top. Finish with a generous drizzle of honey. Make Ahead: You can cook the crepes and store them in the refrigerator, stacked between pieces of waxed or parchment paper, for up to 3 days. You can also freeze them for up to 3 months by allowing the crepes to cool completely, wrapping them well in plastic wrap, and placing them in an airtight container. To reheat, place them in a glass baking dish or a pie plate covered with aluminum foil. Heat in a 250°F oven until just warmed through.